Through the wash hand dish washing products are often sold in liquid form. Although widely used, bulk liquid product forms may have associated issues in terms of packaging, storage, transportation and/or convenience of use. For example, liquid dishwashing products are typically sold in bottles which may add significant cost to the finished product. Additionally, liquid dish washing products may comprise a substantial amount of water in the formula. The high water content increases the bulk of the product which may in turn adversely impact the associated shipping and storage costs. Additionally, liquid dish washing products can be messy. This messiness may cause inconvenience to the consumer when attempting to meter out an accurate dose as it may result in drips and residue on the outside of the bottle. With particularly compact liquids, product may remain upon dosing around the cap.
Liquid dish washing formulations often comprise relatively high levels of surfactants and polymers which may also result in physical stability challenges including, but not limited to, phase separation, gelling and creaming, any of which may lead to a shorter shelf life. Compatibility of these and other actives in a hand dishwashing formulas can be challenging due to for example: differences in the optimum pH of the actives; poor solubility of the actives leading to precipitation in the product; chemical instability of the active due to e.g., surfactant-polymer interactions which may lead to undesirable rheological aesthetics such as stringiness or gelling of the product. Further, it is desirable to be able to formulate enzymes into such product; however the presence of enzymes in liquid products often requires additional stabilizing aids to render them stable upon storage, which in turn adds to the overall cost of the formulation.
Water soluble pouches, such as those made of polyvinyl alcohol are known; however a further issue with such pouches is that they may have a tendency to burst upon storage, particularly if moisture is transferred onto the pouch, via, for example damp hands reaching into the pack of pouches. Multicompartment pouches are known, and are sometimes used to separate physically or chemically incompatible actives or additional benefit agents; however this may lead to a costly process. Tablets are also known; however an issue with such tablets is that they may have a tendency to crumble (e.g., upon transportation) owing to their brittleness.
The aforementioned issues may be addressed by providing a liquid formulation in the alternative form of a porous dissolvable solid structure containing little or no water. For example, such an article could be packaged as a single unit or in multiple units and shipped at a lower cost as compared to the traditional liquid form equivalent. Such an article could eliminate the difficulty and mess associated with handling a liquid dishwashing formulation since no metered pouring would be required. Moreover, many of the stability issues of the liquid form would be eliminated via physical separation such that actives could be combined in new ways that were heretofore impractical and/or impossible.